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javascriptxmlajaxbackbone.js

BackboneJS with XML ajax


this is a two part question from a JS newbie.

So, I was trying to create a backbone application using requireJS by following Thomas Davis's tutorial.

  1. How do I go create Backbone collections out of an ajax call to a server that provides data in XML? collections.fetch() seem to be expecting a JSON backend.

  2. while trying some things, I ended up with the following code, in which the page doesn't refresh upon populating the collection "bookStore" from within Ajax success-callback.

    Here is how far I have gotten so far.

    var bookListView = Backbone.View.extend({
        el: $("#books"),
        initialize: function () {
            thisView = this;
            $.ajax({
                type: "GET",
                url: "books.xml",
                dataType: "xml",
                success: function (data) {
                    console.log(data);
                    $(data).find('book').each(function (index) {
                        var bookTitle = $(this).find('name').text();
                        bookStore.add({ title: bookTitle });
    
                        console.log(seid);
                    });
                    thisView.collection = bookStore;
                    thisView.collection.bind('add', thisView.tryBind);
    
                }
            }).done(function (msg) {
                alert("Data retrieved: " + msg);
            });
    
            this.collection = bookStore;
            this.collection.bind("add", this.exampleBind);
            this.collection.bind("refresh", function () { thisView.render(); });
            /*
            // This one works!
            bookStore.add({ name: "book1" });
            bookStore.add({ name: "book2" });
            bookStore.add({ name: "book3" });
            */
        },
        tryBind: function (model) {
            console.log(model);
        },
        render: function () {
            var data = {
                books: this.collection.models,
            };
            var compiledTemplate = _.template(bookListTemplate, data);
            $("#books").html(compiledTemplate);
        }
    });
    

Here, the success call-back in the "initialize" function seems to be processing the data properly and adding to the collection. However, the page doesn't refreshed.

While I was stepping through the Firebug console, the page gets refreshed however. How do I solve this problem?


Solution

    1. You can override the default parse function to provide XML support. It should return the data transformed into JSON http://backbonejs.org/#Collection-parse

    2. Bind the render to a reset event instead of refresh for Backbone<1.0 or to a sync event for Backbone>=1.0

    It could look like this

    var Book = Backbone.Model.extend();
    
    var Books = Backbone.Collection.extend({
        model: Book,
        url: "books.xml",
    
        parse: function (data) {
            var $xml = $(data);
    
            return $xml.find('book').map(function () {
                var bookTitle = $(this).find('name').text();
                return {title: bookTitle};
            }).get();
        },
    
        fetch: function (options) {
            options = options || {};
            options.dataType = "xml";
            return Backbone.Collection.prototype.fetch.call(this, options);
        }
    });
    
    var bookListView = Backbone.View.extend({
        initialize: function () {
            this.listenTo(this.collection, "sync", this.render);
        },
    
        render: function () {
            console.log(this.collection.toJSON());
        }
    });
    
    var bks = new Books();
    new bookListView({collection: bks});
    bks.fetch();
    

    And a demo http://jsfiddle.net/ULK7q/73/